A belt fastener generally includes an upper plate overlying one side of the belt end and a lower plate underlying the other side of the belt end. The upper plate contains apertures aligning with corresponding apertures in the lower plate located on the opposing side of the belt. The belt fasteners are connected to the belt ends with rivets having a head secured against the upper plate of the belt fastener, a shank passing through an aperture in the upper plate and the belt material, and a swage end passing through the corresponding aperture in the lower plate of the belt fastener and deformed around the aperture.
Optimal belt performance is related to proper connection between the belt ends, and, therefore, is related to a proper connection between the belt fasteners with the belt end. Alignment of the rivets with the corresponding apertures on the upper and lower plates of the belt fastener is critical to ensuring a proper connection of the belt fastener to the belt end. One manner known for aligning the rivets prior to and during driving of the rivets is to utilize a guide assembly containing a guide block. Applicants have developed such assemblies, as shown in U.S. Pat. No. 7,493,682, as well as divisional application Ser. Nos. 12/348,227, and 12/348,229, each of which are incorporated by reference as if reproduced in their entirety herein.
As known in the prior art, the guide block contains a plurality of pilot holes. The pilot holes are arranged to correspond to a predetermined arrangement of apertures in the belt fasteners. The guide block is placed over the belt fasteners in a manner aligning the pilot holes with the belt fastener apertures. A single rivet assembly, which includes the rivet and a detachably connected pilot nail, is loaded into a pilot hole, properly aligning the rivet assembly with the belt fastener aperture prior to and during installation. Each rivet assembly may be loaded individually into a pilot hole, a process taking a considerable amount of time. For example, a standard 48″ belt splice may require approximately 270 rivet assemblies, thus requiring more time to load the pilot holes with rivet assemblies than to actually drive the rivets into the belt end.
In order to facilitate the loading of rivet assemblies into the pilot holes of a guide block, several apparatuses have been developed that hold a plurality of rivet assemblies in a predetermined configuration corresponding to the pilot holes. The prior rivet holders were made of a molded, rigid plastic which contain a number of openings. Rivets were inserted into the mold prior to injection of the plastic material into the mold that formed the rivet holders. The complexity of the mold makes such a process expensive to manufacture. Further, different rivet sizes and compositions required different molds in order to identify the rivets retained in the strip, and further adding to the already expensive manufacturing process.
Additionally, in prior rivet holders, a frangible portion of plastic material may be located on the underside of the rivet head to retain the rivet head within the rivet holder before the rivet head is released from the rivet holder. When force is applied to drive the rivet, the frangible portion of plastic breaks off from the rivet holder, permitting the rivet head to pass freely into the pilot hole of the guide block. The frangible portion may often enter the pilot hole of the guide block prior to the rivet head passing through the pilot hole. Each pilot hole is generally tapered inwardly and only slightly larger than the diameter of the rivet head, configured as such to prevent lateral movement of the rivet during driving. The debris created due to released frangible portions of plastic material in the pilot holes of the guide block can, among other things, restrict the rivet from freely passing through the pilot hole during installation or cause the rivet to seat improperly.
The rivet head is fully retained and concealed within the plastic material after the mold has been filled. This plastic material used in prior molded rivet holders obstructs viewing of the top of the rivet head. A drive head portion of the strip may be molded above the rivet head to facilitate the release of the rivet from the strip when a driving force is applied. The drive head prevents proper identification of the variable length and metal composition characteristics of the individual rivet assemblies because the common method for rivet manufacturers to identify the rivets is to stamp such characteristics on the top of the rivet head. Additionally, drive heads that have been struck by the driving force release from the strip, creating additional build-up of plastic debris during installation.
Because of issues attendant the use of prior rivet holding apparatuses, there has been a need for an improved apparatus for loading rivet assemblies into a guide block prior to installing the rivets into a belt fastener for conveyor belts.